Tumors of the meninges (differential)

Dural masses:

meningiomas and their mimics. Typical meningioma. a Axial T2-weighted MR image of a well-circumscribed meningioma indenting the cortex with a small cleft of CSF. b Coronal post-contrast T1-weighted image showing uniform enhancement, an enhancing-thickened dural tail and hyperostosis of the overlying calvarium. c Unenhanced CT illustrating the adjacent hyperostosis of the skull. d Magnetic resonance spectroscopy of a similar meningioma demonstrating a high choline:creatine (Cho:Cr) ratio and a low N-acetylaspartate (NAA) peak

Dural masses:

meningiomas and their mimics. Atypical meningioma. a, b Pre- and post-contrast axial T1-weighted MR images showing a heterogeneously enhancing mass with a wide dural base, CSF cleft and bony involvement. The cortical interface is less distinct when compared with Fig. 1, and there is a moderate amount of associated vasogenic oedema. c Axial T2-weighted MR image of the same lesion. d Susceptibility-weighted images show internal calcification

Dural masses:

meningiomas and their mimics. Atypical meningioma. a, b Pre- and post-contrast axial T1-weighted MR images showing a heterogeneously enhancing mass with a wide dural bass, dural tail and CSF cleft. The cortical interface is poorly outlined suggestive invasion of the underlying brain parenchyma as well as the adjacent skull. c Axial T2-weighted MR image of the same lesion with surrounding vasogenic oedema and midline shift. d A diffusion-weighted image shows heterogeneous areas of restricted diffusion extending into the adjacent cortex

Dural masses:

meningiomas and their mimics. Breast cancer metastasis. a Post-contrast axial CT showing a strongly enhancing extra-axial lesion with a wide dural base and associated vasogenic oedema. There is no bony hyperostosis or erosion. b T2-weighted axial image of the same lesion which has an indistinct cortical interface suggestive of involvement. c Post-contrast axial T1-weighted MR image of the lesion with some slight heterogeneous but strong enhancement. d Diffusion-weighted imaging demonstrated intermediate restricted diffusion within the lesion

Dural masses:

meningiomas and their mimics. Non-germ cell seminoma metastasis. a Sagittal unenhanced CT image showing an irregular and hyperdense extra-axial mass with a wide dural attachment and only minimal vasogenic oedema. b Sagittal CT image on the bone windowing showing bony destruction adjacent to the lesion (white arrowheads) and no hyperostosis. c Post-contrast sagittal T1-weighted MR image showing only minimal irregular peripheral enhancement and no dural tail. The sagittal sinus is involved and occluded. On unenhanced T1-weighted images, the lesion was isointense to white matter and contained small areas of T1-shortening consistent with haemorrhage. d Coronal T2-weighted image of the same lesion

Primary

extraosseous dural chondrosarcoma: a case report. Axial brain-parenchyma (a) and bone windows (b) of brain in non-enhanced CT demonstrating a parietal mass with subtle hyperostosis and internal calcifications. Axial T2 WI (c,d) shows a lobulated mass which is predominantly hyperintense but with some foci of low signal. Significant mass effect and subtle edema is noted. T1-WI postcontrast (e) and axial T2* MRI perfusion (f) images show a heterogeneous enhancement with honeycomb pattern and low CBV of the tumor